Biomaterial Database

Amino acid sequence of the ribosomal protein L21 of Escherichia coli. 1979

I Heiland, and B Wittmann-Liebold

The primary structure of protein L21 from the 50S subunit of Escherichia coli ribosomes has been completely determined by sequencing the peptides obtained by digestion of L21 with trypsin before and after modification of the arginine residues with 1,2-cyclohexanedione, Staphylococcus aureus protease, thermolysin, and pepsin. Automated Edman degradation using a liquid-phase sequenator was carried out on the intact protein as well as on a fragment arising from cleavage with cyanogen bromide. Protein L21 consists of a single polypeptide chain of 103 amino acids of molecular weight 11 565. An estimation of the secondary structure of protein L21 and a comparison with other E. coli ribosomal protein sequences are presented.

UI	MeSH Term	Description	Entries
D010434	Pepsin A	Formed from pig pepsinogen by cleavage of one peptide bond. The enzyme is a single polypeptide chain and is inhibited by methyl 2-diaazoacetamidohexanoate. It cleaves peptides preferentially at the carbonyl linkages of phenylalanine or leucine and acts as the principal digestive enzyme of gastric juice.	Pepsin,Pepsin 1,Pepsin 3
D010446	Peptide Fragments	Partial proteins formed by partial hydrolysis of complete proteins or generated through PROTEIN ENGINEERING techniques.	Peptide Fragment,Fragment, Peptide,Fragments, Peptide
D010447	Peptide Hydrolases	Hydrolases that specifically cleave the peptide bonds found in PROTEINS and PEPTIDES. Examples of sub-subclasses for this group include EXOPEPTIDASES and ENDOPEPTIDASES.	Peptidase,Peptidases,Peptide Hydrolase,Protease,Proteases,Proteinase,Proteinases,Proteolytic Enzyme,Proteolytic Enzymes,Esteroproteases,Enzyme, Proteolytic,Hydrolase, Peptide
D011487	Protein Conformation	The characteristic 3-dimensional shape of a protein, including the secondary, supersecondary (motifs), tertiary (domains) and quaternary structure of the peptide chain. PROTEIN STRUCTURE, QUATERNARY describes the conformation assumed by multimeric proteins (aggregates of more than one polypeptide chain).	Conformation, Protein,Conformations, Protein,Protein Conformations
D002855	Chromatography, Thin Layer	Chromatography on thin layers of adsorbents rather than in columns. The adsorbent can be alumina, silica gel, silicates, charcoals, or cellulose. (McGraw-Hill Dictionary of Scientific and Technical Terms, 4th ed)	Chromatography, Thin-Layer,Thin Layer Chromatography,Chromatographies, Thin Layer,Chromatographies, Thin-Layer,Thin Layer Chromatographies,Thin-Layer Chromatographies,Thin-Layer Chromatography
D003488	Cyanogen Bromide	Cyanogen bromide (CNBr). A compound used in molecular biology to digest some proteins and as a coupling reagent for phosphoroamidate or pyrophosphate internucleotide bonds in DNA duplexes.	Bromide, Cyanogen
D004926	Escherichia coli	A species of gram-negative, facultatively anaerobic, rod-shaped bacteria (GRAM-NEGATIVE FACULTATIVELY ANAEROBIC RODS) commonly found in the lower part of the intestine of warm-blooded animals. It is usually nonpathogenic, but some strains are known to produce DIARRHEA and pyogenic infections. Pathogenic strains (virotypes) are classified by their specific pathogenic mechanisms such as toxins (ENTEROTOXIGENIC ESCHERICHIA COLI), etc.	Alkalescens-Dispar Group,Bacillus coli,Bacterium coli,Bacterium coli commune,Diffusely Adherent Escherichia coli,E coli,EAggEC,Enteroaggregative Escherichia coli,Enterococcus coli,Diffusely Adherent E. coli,Enteroaggregative E. coli,Enteroinvasive E. coli,Enteroinvasive Escherichia coli
D000595	Amino Acid Sequence	The order of amino acids as they occur in a polypeptide chain. This is referred to as the primary structure of proteins. It is of fundamental importance in determining PROTEIN CONFORMATION.	Protein Structure, Primary,Amino Acid Sequences,Sequence, Amino Acid,Sequences, Amino Acid,Primary Protein Structure,Primary Protein Structures,Protein Structures, Primary,Structure, Primary Protein,Structures, Primary Protein
D012269	Ribosomal Proteins	Proteins found in ribosomes. They are believed to have a catalytic function in reconstituting biologically active ribosomal subunits.	Proteins, Ribosomal,Ribosomal Protein,Protein, Ribosomal
D013820	Thermolysin	A thermostable extracellular metalloendopeptidase containing four calcium ions. (Enzyme Nomenclature, 1992) 3.4.24.27.	Thermolysin S